How to reference this variable (nested objects/arrays)?

I'm learning PHP and Drupal. I need to reference a variable contained in an array called $contexts.

So print_r($contexts) gives me this:

Array ( 
   [context_view_1] => ctools_context Object ( 
       [type] => view 
       [view] => view Object ( 
          [db_table] => views_view 
          [result] => Array ( 
              [0] => stdClass Object ( 
                   [nid] => 28 
                   [node_data_field_display_field_display_value] => slideshow
              ) 
           )

eek confusing. I want to work with the node_data_field_display_field_display_value variable. I think my code ne开发者_如何学编程eds to be like this, but I know this isn't right:

if ($contexts['context_view_1']['view']['result'][0]
['node_data_field_display_field_display_value'] == 'slideshow') then do whatever...

Thanks!

You suggested the following array reference to get to the variable you want:

 $contexts['context_view_1']['view']['result'][0]['node_data_field_display_field_display_value']

The reason this doesn't work is because some of the structures in the chain are actually objects rather than arrays, so you need a different syntax for them to get at their properties.

So the first layer is correct, because $contexts is an array, so context_view_1 is an array element, so you'd get to it with $contexts['context_view_1'] as you did.

But the next level is an object, so to get to view, you need to reference it as an object property with -> syntax, like so: $contexts['context_view_1']->view

For each level down the tree, you need to determine whether it's an object or an array element, and use the correct syntax.

In this case, you'll end up with something that looks like this:

$context['context_view_1']->view->result[0]->node_data_field_display_field_display_value

That's a mess of a variable. The issue you're having is that you're using the bracketed notation, e.g. "['view']", for each "step" in the navigation through your variable. That would be fine if each child of the variable were an array, but not every one is.

You'll note, for example, that $contexts['context_view_1'] is actually an object, not an array (take note that it says "[context_view_1] => ctools_context Object"). Whereas you would use that bracketed notation to address the elements of an array, you use the arrow operator to address the properties of an object.

Thus, you would address the field you are trying to reach with the following expression:

$contexts['context_view_1']->view->result[0]->node_data_field_display_field_display_value

For properties listed as "Object", you need to use -> to get into it, and "Array", you need to use []. So:

$contexts['context_view_1']->view->result[0]->node_data_field_display_field_display_value

$contexts['context_view_1']->view->result[0]->node_data_field_display_field_display_value

echo $context['context_view_1']->view->result[0]->node_data_field_display_field_display_value;

Do not mistake objects with arrays. A memeber of an array can be accesed by $array['member'], but fields of an object can be accessed as $object->fieldname.